The present invention is in the field of vents built into the foundation walls of buildings with crawl spaces and the like that need passive venting.
Houses and buildings with crawl space type spaces are typically provided with vents in the exposed foundation wall around the crawl space to prevent moisture build-up and damage. These crawl space or xe2x80x9cfoundationxe2x80x9d vents are cemented or otherwise permanently secured in openings left in the block or cement wall at the time of construction, the openings in the wall providing for a flow of air to and from the crawl space. The vents typically have a grille and/or screen or mesh face to keep rodents and insects out and often have closeable louvers or dampers to seasonally adjust airflow in colder climates.
Theoretically, the closeable-type vents are left open in warmer weather to keep the crawl space vented and dry, and in colder climates closed for the fall/winter to keep the crawl space (and the floor of the house) warm. However, the adjustment mechanisms in these vents are often relatively complex and prone to damage or failure through abuse such as being painted over, banged with lawn equipment, and exposed to the elements. The vents can accordingly become difficult to adjust properly and can even get stuck in one position. Over time the damage and wear accumulate, making the original unattractive and ripe for replacement. However, calling a contractor in for the relatively minor but time-consuming task of replacing one or more original, cemented-in vents can be inordinately expensive.
Since the vents are cemented or otherwise permanently secured in the foundation wall around the perimeter of the crawl space (often a considerable distance from the crawl space access in the house or building), it can be a cold, dirty crawl to try to repair, close, seal, and sometimes even insulate the vents from the inside. Accordingly, one can often see plastic sheeting, insulation boards and hay bales mounted and piled at unsightly intervals around the foundations of houses with crawl spaces in colder climates as homeowners try to slow down the wasteful, expensive, and uncomfortable heat loss from their homes via the crawl space vents, and to reduce the corresponding potential for frozen pipes. U.S. Pat. No. 6,149,514 attempts to partially solve the problem with a cut-to-size, snap-on, insulated cover, with snap-fittings secured to the foundation wall around the cemented-in vent to receive the insulated cover.
Another disadvantage of conventional closeable crawl space vents is the relatively limited ventilation area they offer for a given size when maximum venting is desired, since the louvers and associated support and adjustment structure reduce the net venting area of the screen or mesh and obstruct airflow.
The present invention is a crawl space vent assembly that can be opened in warmer weather for nearly unrestricted venting, partially restricted for reduced venting in cooler weather, or even sealed tightly and/or insulated in the coldest weather or where pipes run near a vent opening, all from the outside of the house. In a first and preferred embodiment the vent assembly is designed to be retrofit to an existing crawl space vent opening after removing the original conventional vent. The retrofit embodiment also lends itself to drop-in installation for new construction. The vent is damage-resistant and easily adjusted and repaired.
In a second embodiment the vent is specifically designed for drop-in installation in a new foundation wall during construction.
In general, the vent assembly has a front frame adapted to engage the face of the foundation wall around the front of the vent opening; a set of swappable venting plates easily installed on and removed from the front frame member from the exterior of the house for different levels of venting; a screen associated with the venting plates; and a rear frame connectable to the front frame through the opening under tension to secure the vent assembly solidly to the front and rear faces of the foundation wall. The rear frame preferably includes a cross-member spanning the opening, able to retain an optional volume of insulation added to the vent through the front frame, minimizing airflow obstruction when insulation is not present, and providing an aligned-with-the-opening handgrip for an installer working from the outside to position the rear frame relative to the tension member(s) in the crawl space. If more than one cross-member is used, space is provided between the members for an outside installer to insert a hand through the rear frame.
In the preferred form the front and rear frames are adjustably connected to one another to be pre-positioned in the opening and then tensioned against the outside and inside faces of the wall around the vent opening. The adjustable frames can be made sufficiently adjustable to accommodate variations in wall thickness.
In the preferred, retrofit embodiment of the invention, the vent assembly has a collapsible rear frame designed to be inserted through the pre-positioned front frame and vent opening from the outside and opened up inside to engage one or more adjustable tension members extending from the front frame. The rear frame is then tensioned against the wall using the tension members connected to the front frame. In a most preferred form of this embodiment, the rear frame is a pair of pivoting members, sized to be inserted through the wall opening when folded and then opened to span the opening and engage the inside wall around the opening. The assembly is sufficiently rigid on its own that it can even be installed in drop-in fashion in new construction.
The second, drop-in embodiment of the vent is specifically designed for original installation in a new foundation wall, and includes an intermediate boxlike body connecting the front and rear frames. In a preferred version the body is adjustable to tension the front and rear frames against the inner and outer faces of the wall around the opening, and optionally to accommodate different wall thicknesses.
In a first form, the front frame receives the venting plate in axial, stack-on fashion. In a preferred form the front frame includes a venting plate receiver panel with an interlocking insertion fit that lends itself to aligning and holding the receiver in place for hands-free final securing. The receiver panel is easily removed from the front frame for repair, maintenance and/or replacement of interior components and venting plates. The preferred form of the receiver panel tilts open for a smooth release from the front frame, and includes a lateral slot for slidably receiving a venting plate from one end. The receiver panel also preferably includes a second lateral slot for slidably receiving a removable and replaceable screen member. The receiver panel supports and protects the venting plate and especially the screen from damage, but in the event they are damaged, they are each easily replaced.
Another feature of the invention is found in the venting plate vent openings, which are intended to overlie the screen and which have successively smaller, coaxial openings from plate to plate.
These and other features and advantages of the invention will become apparent upon further reading of the specification in light of the accompanying drawings.